Vacuum ignition control



. July 30,1935. M. MALLO'RY 2,009,933

VACUUM IGNITION CONTROL Filed March 27, 1933 mmm INVENTOR ATTORNEY Patented' July 30, 1935 PATENT OFFICE cocasse vAcUUM iGNirioN com-no1.

Marion Mallory, Detroit, Mich., assignorto The Mallory Research Company, Toledo, Ohio, a corporation of Delaware Application Maren 27, isaseriai No. 662,987

4 Claims.

The object of this invention is to improve the automatic control of the ignition of an internal combustion engine. See Nickerson, #1,139,707 issued May 18, 1915.

5 The speciiic objects are:-'

(a) To positively and instantaneously retard the spark when-the engine is idling.

(b) To prevent the engine, to which the device is attached, from hunting. Hunting is due to l0l the delay in the action of a governor or any other automatic controlling device so that when the controlling device comes into action, the conditions calling it into action have already been acting long enough so that it is too late for the control mechanism to prevent the engine either racing or slowing down beyond the desired' degree. This, of course, causes a surge in the speed.

(c) To minimize any air leakage, which is usually associated with'the devices of the type shown in the Nickerson patent, in which a vacuum controlled piston moves the circuit breaker of the ignition system. This leakage is from the atmosphere to the inlet manifold ofthe engine with which the ignition control device of the Nickerson type is associated. In the iiguresz- Fig. 1 shows diagrammatically the installationof the preferred form of my invention in combination with an existing timer, which may or may not becentrifugally controlled.

Fig. 2 shows a modication of my invention.

In Fig. 1, II is the vacuum pipe connecting the inlet manifold I2' of the internal combustion engine (not shown) with the automatic ignition device. 'I'he pipe II enters the inlet manifold I2 above the throttle I 3 so that the device is subjected t0 the vacuum on the engine side of the throttle. is the control device, which is used to modify the action of the well-known Nickerson device referred to above. In M, a 4cylindrical valve Il is provided with an annular groove I5, which acts as a passage connecting the pipe I I with the passage It. 'I'his passage IG communicates the v acuum from the inlet manifold I2 to the Nickerson ignition control device, which consists of:-

A cylinder I'I, a piston Il, a cylinder cover 31 opentto the atmosphere at 36, a piston rod 2l, a stop r28, a pulley 29, a wire 30 anchored at ,40 to some part of the car or engine. A spring 32 opposes the movement of the piston Il under the influence of the suction in I2. A circuit breaker I9 is shown controlled by the wire 30.

This circuit breaker Il may be associated with vany of the well known centrifugal devices, such (Cl. 12S-117) as that shown in the patent of Kent #1,192,788, which was issued July 25, 1916.

When the piston I8 moves over to the left, it restricts the leakage of air into the inlet manlfold I2, as the end of I8 restricts the iiow of' air o through is.

Considering the novel feature of the control device 44 more in detail, the valve Il is located in the cylinder 2|, which is in open communication with the atmosphere through an opening 22.- l0Y At the other end, it is closed by an adjustable stop 23, which is the means provided for controiling the action of the piston` I4. The spring 24 engages at one end with this adjustable stop 22, and at theother end with the piston I4.. The l5 spring has sufficient length so that the valve Il responds promptly to the critical changes oi vacu um, which occui under certain conditions oi speed and load.

A seat 25 limits the travel of theplston Il.

26 is an atmospheric by-pass, which admits air from the port 22 to the cylinder I1 through the .passage I6, when the vacuum II is high enough to draw the-piston or valve Il soa-as to uncover' the passage 26, and at the same time cut ol the 25. communication from II to I6 through the annular groove I5. 'I'he operating vacuum, which causes the piston Il to move, is communicated to the opposite side of the valve I4 through the vacuum by-pass 21, which communicates with the 30 passage Il and the interior of the cylinder 2l.

In Fig. 2, two extra grooves 3l and ll are` provided in the piston Il. The lower groove 24 is so located that, when raised during the idling ol the engine, a passage in the wall of the cylin- 25 der 2I is put in communication with the passage I6.

The upper groove 321s so located that, when raised by a vacuum exceeding the idling vacuum, the vacuum is readmitted into the cylinder II Q0 and the ignition is once more advanced by reason of the action of the vacuum. When the vacuum is readmitted, the adjustment 23 is adjusted so that the valve I4 does not rise far enough to uncover the port 2,`and to admit air so as to neutralize the vacuum readmitted to II through the annular port 33.

Operation When the engine is idling, the vacuum is admitted from I2 to the passage 21, which acts on the piston I4, which rises against the compression of the spring 24; the vacuum in 21 being aided by the atmospheric pressure acting through 22.

and I6. It also opens the passage 26 to the atmosphere which enters at 22. Atmospheric air then rushes into the cylinder I'I and pushes the piston I8 over to the right, and thereby retards the spark without the slightest delay, which delay causes an unpleasant sensation and unsteady running of the engine.

As shown in Fig. 2, when the engine is idling, the piston I4 is raised only far enough for the groove 34 to open-communication between the atmospheric port 35 and the lower branch of the passage I6, thereby allowing the piston I8 to move to the right so that the spark is retarded. When the car is coasting at high speed, however, with the clutch in and the engine revolving at high speed, an excessive vacuum is created and the piston I4 is raised higher, until the port 35 is closed and the groove 33 opensV communication between the pipe II and the upper b ranch of the passage I6, thus again moving the piston I8 to the left and again'advancing the spark. A high vacuum leads to slow flame propagation. Hence, if the high vacuum is associated with high speed and a retarded ignition, very irregular ignition will result, accompanied by backiring and muilier explosions.

Again, when the car is coasting at high speed on the level and the car is driving the engine, if

the spark is retarded, the engine will act as a brake on -the car, which will lead to excessive fuel consumption. In any event, it is desirable to advance the ignition at all times with a high vacuum except when idling. The further one coasts, the less fuel is used, as every time the throttle is opened, the carburetor accelerating pump discharges its accelerating fuel charge.

By idling is meant the running of the engine with throttle closed and no load on the engine.

What I`claim is:

l. Ignition control means for an internal combustion engine, baving'a fuel inlet manifold and a throttle valve therein, comprising a fuel inlet vacuum responsive device, an ignition timing'device connected therewith and adapted tobe advanced thereby whenthe vacuum increases, a piston valve for controlling the admission of vacuum to said device, a cylinder having a closed end in which said valve reciprocates, one end of said cylinder being open to the atmosphere, a passage connecting the closed end with the inlet vacuum,

spring means engaging with said piston inopposition to said vacuum, a port in the wallet said cylinder communicating with said device and controlled by said piston so as to be closed when the vacuum overcomes the spring and to be opened to admit the vacuum from the inlet manifold to said device at other times, a second port in the wall of said cylinder communicating with the atmosphere and with said device, said port being controlled by said piston so as to be opened to admit atmospheric air to said device when the first port is closed.

2. A device as claimed in claim l with, an additional port in said piston adapted to engage with the rst port in said cylinder to readmit the vacuum. to said device, an extension in said piston to close the second port in said cylinder when the vacuum is readmitted through the additional port in said cylinder.

3. In an ignition control device of the type in which the engine suction advances the ignition, an automatic suction control valve comprising a cylinder, a piston reciprocating therein, means for admitting suction to one end of the cylinder, means for admitting atmospheric pressure to the other, spring means for opposing the movement f the piston due to the difference in pressure, a passage admitting suction to said ignition control device-y said piston forming a movable obstruction in said passage, a passage admitting atmospheric air to said ignition control device, said piston also forming a movable obstruction in said passage, whereby the suction is automatically disconnected from said ignition control device and the atmospheric pressure is suddently admitted when the suction reaches va predetermined value corresponding to idling suction.

4. In an internal combustion engine, having an air inlet manifold and a throttle admitting air thereto, lthe combination with an ignition timing mechanism of a Vacuum responsive controlling means therefor mechanically connected thereto and a valvecontrolling the admission of vacuum to said means from the inlet manifold on the en.- gine side of the throttle, said valve being also controlled from the vacuum between the throttle and the engine, yielding means for opposing said valve, Y

a passage for admitting atmospheric air to said.

vacuum responsive means and also controlled by said valve, whereby the vacuum is cut off and atmospheric pressure is admitted when the vacuum in' the inlet manifold reaches a predetermined value.

` MARION MALLORY. 

